Cobalt-concanavalin A. An index of inactive and active conformational states

Studies on the circular dichroic spectrum of cobalt-substituted concanavalin A have been continued in particular with respect to calcium- and saccharide-induced spectral pertubations reported previously (Kalb, A.J. and Pecht, I. (1973) Biochim. Biophys. Acta 303, 264-268; Richardson, C.E. and Behnke, W.D. (1976) J. Mol. Biol. 102, 441-451). We find that the addition of calcium or cadmium to (CO2+)-concanavalin A induces slow time-dependent alterations in the extrinsic cotton effects. Moreover, one equivalent of calcium is sufficient to cause maximal changes in the cobalt spectrum provided sufficient time is allowed for the effect to be observed. The addition of mono, di-and trisaccharides, specific for concanavalin A, have no resolvable effect upon the cobalt spectrum of concanavalin A (Richardson, C.E. and Behnke, W.D. (1976) J. Mol. Biol. 102, 441-451). The data presented here suggest that these time-dependent processes are conformationally mediated and occur subsequent to S2 occupancy. Evidence is presented that a particular calcium-cobalt-concanavalin A conformer exists which is responsible for the generation of activity in a light-scattering assay system.     

Nonlactating-cow therapy with a formulation of penicillin and novobiocin: therapeutic and prophylactic effects

An experimental product incorporating 500,000 IU of procaine penicillin G and 600 mg of sodium novobiocin in 2% aluminum monostearate-peanut oil gel (10-ml dose) was infused after the final milk-out at end of lactation into all 4 mammary quarters of 56 cows that were infected in at least 1 quarter. The therapeutic and prophylactic efficacies were published in the companion report. Infusion of the product in all quarters of 5 lactating cows resulted in only slight irritation. Penicillin was eliminated by the 11th milking and novobiocin by the 5th. After infusion in the dry udder, the antibiotics were no longer detectable in serous secretion after 14 days and failed to appear in urine at the earliest (7-day) sampling after administration. Neither antibiotic was detectable in the 1st postpartum milking after nonlactating periods as short as 3 weeks.     

Use of intra-aortic balloon pumping (IABP) in clinical cardiac surgery and management of patients with IABP

One hundred thirty eight patients were reviewed which required IABP assist. Sixty nine (84 per cent) of 82 patients who had been able to come off cardiopulmonary bypass despite increasing pharmacologic support survived operation and 56 patients (68 per cent) discharged hospital. Twenty three (75 per cent) of 31 patients who took for elective coronary artery surgery as extremely high risk because of extensive three vessel coronary artery disease and severely compromised left ventricular function discharged hospital. In summary, hospital death was 35 per cent, late death 12 per cent and long term survivors 54 per cent. Severe complication concerned with inserting balloon catheter occurred in two cases (1.4 per cent) which were abdominal aortic dissection and laceration of iliac artery. At the present time, the primary indication for IABP is in assistance of the open heart surgical patient. Thre are three important factors in successfully managing the patients with IABP. First, begin IABP assist as soon as possible if indicated. Second, keep an adequate circulating volume with mean left atrial pressure being maintained around 20 mmHg and cardiac index at 2.1 L/min./M or greater. Third, improve the peripheral vascular circulation, which might need peripheral vasodilator.     

How well does number of parents explain unique variance in self-reported drug use?

Data from an anonymous survey of 3,690 adolescents were used to assess how much of the unique variance in adolescents' self-reported drug use was accounted for by number of parents in comparison to the adolescents' sex, age, social class, and peer drug use. Multiple regression revealed that the contribution of number of parents was small and nonsignificant compared to peer use, student age, parental occupation and remarriage, student sex, and parental unemployment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)